Conservative delegates at the party's policy convention in Vancouver have voted to strike the definition of marriage in the party's official policy document.
In a 1,036-462 vote, delegates from all provinces except Saskatchewan cast majority votes in favour of no longer defining marriage as a union between one man and one woman.
"I think our party got a little more Canadian today," Calgary MP Michelle Rempel said after the vote. "It's a milestone and it's not just a milestone for our party, it's a milestone for all Canadians."
"Yes, it took us 10 years to get to this point, but I think this is something that is a beacon for people around the world who are looking at equality rights. Canada is a place where we celebrate equality."
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The result followed a heated debate and prompted some high-fives and cheers across the hall. It shifts the party's official position on same-sex marriage from being against the unions to neutral.
Eric Lorenzen, from an Eastern Ontario riding, said during the debate that as a gay Conservative, he found it troubling that his party told him his relationship with his partner was not valued.
"What other group does our party have a negative policy towards? A policy of restricting civil rights and restricting full participation in society?" he said, drawing applause.
"It's all about freedom and respect," said Quebec MP Maxime Bernier. "It's about us and it's about telling Canadians that you can love who you want and that you can be loved... and having fair policies at the federal level for that."
"I'm proud of you to have this debate here with you," the former cabinet minister said.
"'It is a fundamental human right and government does not have a place in your bedroom," said Goldie Ghamari, who is seeking a nomination in an Ottawa riding to run for the Ontario Progressive Conservative Party.
Losing party's base?
Speakers against the motion warned that social conservatives — who make up 40 per cent of the party's base, according to one person — would stay home and stop supporting the Conservative Party if it didn't represent their views on marriage.
"This resolution is not about inclusiveness or the value of individuals," Manitoba MP Ted Falk warned. "This motion is an attack on our values and principles."
But other social conservatives elected to support deleting the definition, calling the wording of the policy a workable compromise because opponents still had the freedom to hold personal opinions against same-sex marriage.
Alberta MP Shannon Stubbs told CBC News she knew of some who held personal views against gay marriage but nevertheless supported the motion. People were ready to move on, she suggested.
Saskatchewan MP Brad Trost, who was vocal in his opposition to the proposal throughout the convention, said he was disappointed. Some of his colleagues had expressed support for traditional marriage and campaigned on it but then said they didn't want to deal with the issue anymore.
"It was a line in the sand. With that line, other things wouldn't be crossed," he said. "I don't see the need to change."
"I didn't get into politics just to vote for the lowest common denominator. I believe in things."
Motions condemning gender-selection abortions, endorsing ticketing rather than arresting individuals found with small quantities of marijuana and protecting conscience rights for medical practitioners who don't want to perform abortions or participate in assisted suicide also passed on Saturday.
None of the 32 resolutions considered by the full group of delegates failed.
'Don't anticipate anyone leaving'
MP Erin O'Toole had predicted Saturday morning that the motion would pass, saying his party was evolving and people were more comfortable with it now.
"We're tackling tough issues — whether it's euthanasia, same-sex marriage — and doing it quite respectfully. We're having passionate debate and then at the end of the day we're having a beer together."
O'Toole added that the Conservative Party is a "brokerage party," where no member expects to have all of his or her positions reflected. "I don't anticipate anyone leaving," he said.
Former cabinet minister Steven Blaney, who opposed same-sex marriage originally, said Canadians have spoken and it was time.
"I haven't met anybody who is passionate about keeping an obsolete policy on the books that no longer reflects law or social custom," possible leadership contender Jason Kenney told The Canadian Press.
'Value of human life' added
On Saturday morning, delegates voted in favour of a half-dozen amendments to the party's constitution, while rejecting one.
The phrase "a belief in the value and dignity of all human life" was added to the party's governing document after a short debate.
Rempel argued that it was a way for the party to stand up against the genocide of Yazidis in Northern Iraq. Another delegate wondered if it was a policy amendment in disguise, suggesting that if the party wanted to adopt language on abortion or assisted suicide, it should do so outright.
Other changes clarified that senators can participate in choosing an interim leader and national councillors must not receive compensation nor get involved in nomination or leadership contests.
The defeated amendment concerned the treatment of donations for the purposes of attending a national convention.
At the convention simultaneously underway for the Liberals in Winnipeg, Prime Minister Justin Trudeau took a shot at Conservatives for debating same-sex marriage more than a decade after a Liberal government made it legal.
"Better late than never," he said. "Who knows … 10 years from now, they might finally be willing to admit that climate change is real. Or that tax cuts for rich people don't help the middle class. Or that government shouldn't legislate what women can wear on their heads."